Package for blasting caps



QWCM UH HUHW rik 1 Apr 1933- J. STUART, 2D

PACKAGE FOR BLASTING' CAPS Filed March 3, 1932 W/T/VESS. WW

EXPLOSIVE DEVICES 3%55Uifi l 't tt tlllfii Patented Apr. 4, 1933 UNITED STATES PATENT OFFICE JOSEPH STUART, 21), OF WILMINGTON, DELAWARE, ASSIGNOR TO HERCULES POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE PACKAGE FOR BLAS'IING- GAPS Application filed March 3, 1932. Serial No. 596,501.

This invention relates to an improvement in package for blasting caps and more particularly relates to a package which will afford improved protection for caps of the type adapted to be fired electrically, not only from physical contacts but also from electrical contacts.

As is well known, blasting caps of the type adapted to be fired electrically comprise essentially a casing suitably charged and a pair of lead wires connected within the cap by means of a bridge wire adapted to fuse on the passage of a current and fire the cap. The lead wires are insulated except at their free end portions which are left bare in order to permit the lead wires to be connected into a circuit.

Blasting caps of the type indicated are sensitive to physical contact or shock since these explosive charges are sensitive and, as ordinarily handled, are liable to accidental firing through contact of the uninsulated end portions of the lead wires with a source of current.

Heretofore blasting caps have been customarily shipped with the cap proper unprotected and with the lead wires bundled together, either without any protection for the uninsulated portions or with some form of shunt device thereon; and it has been customary for users to carry them to the point of use in the pocket or in the hand and frequently with the lead wires unbundled and trailing.

As a consequence of prior methods in the shipping and handling of blasting caps frequent accidents have occurred, either from a blow on the cap or through accidental contact of the uninsulated ends of the lead wires with a circuit or source of stray current.

Now it is the object of this invention to provide a package for blasting caps of such a character as to afford full protection to the cap from physical contacts and to the uninsulated end portions of the lead wires from electrical contacts, while at the same time, providing a package which will be convenient to handle, apply and remove.

Having now indicated in a general way the nature and purpose of my invention, I

50 will proceed to a more detailed description of a preferred embodiment thereof with reference to the accompanying drawing in which:

Figure 1 is a perspective view of a blasting cap with the lead wires thereof in association with an element of the package embodying this invention.

Figure 2 is a perspective view of another element of the package embodying this invention.

Figure 3 is a plan view partly broken away of a package embodying this invention with a blasting cap partially packaged.

Figure 4 is a view similar to that of Figure 3 with the cap completely packaged.

In the drawing A indicates a spool, having a central bore 72 and end flanges 00. D indicates a tubular casing having an interior diameter of such size as to fit snugly over the flanges cc of spool A, and provided with a longitudinal slot 6 enlarged at a point between its ends, as at f. The enlargement of the slot 6, as at f is of such dimensions as to permit the passage of a blasting cap to be packaged.

G indicates a blasting cap of any desired construction and loading, and provided with a pair of insulated lead wires 7th, free end portions 2', i of which are uninsulated.

From an inspection of the drawing the assembly of the elements of the package, including the cylindrical base or spool A and the casing D, and the packaging of the cap will, it is believed, be obvious. However in packa ing the cap it will be noted that the uninsu ated free end portions 2', i of the lead wires hh are applied to the base or spool A adjacent one of the end flanges 0 and the lead wires wrapped about the base and upon themselves covering and acting to protect their uninsulated end portions. When the lead wires, except for a length adjacent to the cap, are wound on the base A, the cap is passed into cover D from one end and through enlargement of slot 6, and the cover D slipped over the base or spool A and the lead wires wrapped thereon to the position, for exam-' ple, as shown in Figure 3. The cap, with the lead wires extended through a slot e adjacent one of its ends, is then inserted into the bore 12 of the spool A, as shown in Figure 4. 100

The cap packaged as described is, as will be obvious, fully protected from physical contact and the uninsulated end portions of the lead wires are likewise fully protected from electrical contact. The casing is maintained in place on the base by the extension of the lead wires through and about an end of the casing.

The package lends itself readily to the packing of caps for storage or shipment and for handling to the point of use of the caps. The cap may be readily removed from the package for use by merely withdrawing the cap from the bore of the spool and unwinding the lead wires while holding the casing in the hand, it being noted that the uninsulated ends of the lead wires are fully protected until completely removed from the spool and that the lead wires when unwound or withdrawn from spool A are straight and unkinked.

What I claim and desire to protect by Letters Patent is:

y 1. In combination a base having a bore exending from one end, a casing for said base provided with a longitudinally extending slot and a blasting cap provided with lead wires, said lead wires being wrapped from their free ends about said base, and said cap being positioned in'the bore therein, said casing being positioned on said base and said lead Wires extending from the cap over one end of the casing and through the slot therein.

2. In combination a base having a bore extending from one end, a casing for said base provided with a longitudinally extending slot and a blasting cap provided with lead wires, said lead wires being wrapped about said'base, and said can being positioned in the bore therein, said casing being positioned on said base and said lead wires extending from the cap over one end of the casing and through the slot therein.

3. In combination a base having a bore extending from one end, a casing for said base provided with an aperture in its side and a blasting cap provided with lead wires, said lead wires being wrapped about said base, and said cap being positioned in the bore therein, said casing being positioned on said base and said lead wires extending from the cap over one end of the casing and through the slot therein.

4. In combination a base provided with flanges at its ends and having a bore extending from one end, a casing for said base pro.- vided with an aperture in its side and a blasting cap provided with lead wires, said lead wires being wrapped about said base, and said cap being positioned in the bore therein, said casing being positioned on said base and said lead wires extending from the cap over one end of the casing and through the slot therein.

5. In combination a base having a bore ex- 

